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Disease Profile

Myelodysplastic Syndrome With Excess Blasts

Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.


US Estimated

Europe Estimated

Age of onset





Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease.


Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype.


dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.


recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder.


Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.


Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.


Not applicable


Other names (AKA)

Refractory anemia with excess blasts; RAEB


Myelodysplastic syndrome with excess blasts is a rare type of myelodysplastic syndrome (MDS).[1] In this type of MDS, the number of very early forms of blood cells (blasts) are increased in the bone marrow and/or blood. There is also a low numbers of at least one type of blood cell. The early forms of cell types in the bone marrow (red blood cells, white blood cells, or platelets) may or may not look abnormal (dysplasia) under the microscope. Signs and symptoms may include a very hard to treat and persistent anemia (refractory anemia), frequent infections (due to low numbers of neutrophils), easy bruising and bleeding (due to low number or abnormal platelets). MDS with excess blasts is one of the MDS most likely to turn into acute myeloid leukemia (AML).[1][2] It is classified into 2 types, based on how many of the cells in the bone marrow or blood are blasts:[1][2][3]

  • MDS-EB1: blasts make up 5% to 9% of the cells in the bone marrow, or 2% to 4% of the cells in the blood 
  • MDS-EB2: blasts make up 10% to 19% of the cells in the bone marrow, or 5% to 19% of the cells in the blood; this type has a higher risk to become AML.

Some cases of MDS are linked to known risk factors (such as smoking, chemotherapy, having a genetic syndrome that increases the chance of developing MDS and other). These factors lead to changes in the DNA in bone marrow cells may cause MDS to develop, but most often, the cause is unknown.[4] Treatment may include blood transfusions, supportive care, chemotherapy, radiotherapy and bone marrow transplant.[2][ 14773][6]


This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Medical Terms Other Names
Learn More:
80%-99% of people have these symptoms
Anemia of inadequate production

[ more ]

30%-79% of people have these symptoms
Anemic pallor
Exertional dyspnea
Missed heart beat
Skipped heart beat

[ more ]

5%-29% of people have these symptoms
Abnormal albumin level
Abnormal mean corpuscular volume
Acute myeloid leukemia
Bone marrow hypocellularity
Bone marrow failure
Bone pain
Chronic infection
Dysplastic granulopoesis
Elevated white blood count
High white blood count
Increased blood leukocyte number

[ more ]

Multiple lineage myelodysplasia
Pedal edema
Fluid accumulation in lower limbs
Lower leg swelling

[ more ]

Retinal hemorrhage
Retinal bleeding
Single lineage myelodysplasia
Low platelet count

Learn more

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

In-Depth Information

  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.


  1. What is myelodysplastic syndrome – Refractory Anaemia with Excess Blasts (RAEB)?. Leukaemia Foundation. https://www.leukaemia.org.au/disease-information/myelodysplastic-syndromes/types-mds/raeb/.
  2. Hasserjia RP. Pathology of Myelodysplastic Syndrome With Excess Blasts. Medscape Reference. March 5, 2018; https://emedicine.medscape.com/article/1997173-overview.
  3. Types of Myelodysplastic Syndromes. American Cancer Society. 2018; https://www.cancer.org/cancer/myelodysplastic-syndrome/about/mds-types.html.
  4. What causes myelodysplastic syndromes. American Cancer Society. January 22, 2018; https://www.cancer.org/cancer/myelodysplastic-syndrome/causes-risks-prevention/what-causes.html.
  5. Wang M, Han HH, Guo R, Liu YF, Jiang ZX & Sun H. Clinical Efficacy of Low-dose Decitabine Combined with CAG Regimen in Patients with Myelodysplastic Syndrome-refractory Anemia with Excess Blasts(MDS-RAEB). Zhongguo Shi Yan Xue Ye Xue Za Zhi. October, 2017; 25(5):1482-1486. https://www.ncbi.nlm.nih.gov/pubmed/29070129.
  6. Locatelli F & Strahm B. How I treat myelodysplastic syndromes of childhood.. Blood. March 29, 2018; 131(13):1406-1414. https://www.ncbi.nlm.nih.gov/pubmed/29438960.